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-rw-r--r--src/gallium/drivers/softpipe/sp_prim_setup.c1247
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diff --git a/src/gallium/drivers/softpipe/sp_prim_setup.c b/src/gallium/drivers/softpipe/sp_prim_setup.c
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+++ b/src/gallium/drivers/softpipe/sp_prim_setup.c
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+/**************************************************************************
+ *
+ * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+/**
+ * \brief Primitive rasterization/rendering (points, lines, triangles)
+ *
+ * \author Keith Whitwell <keith@tungstengraphics.com>
+ * \author Brian Paul
+ */
+
+
+#include "sp_context.h"
+#include "sp_headers.h"
+#include "sp_quad.h"
+#include "sp_state.h"
+#include "sp_prim_setup.h"
+#include "pipe/draw/draw_private.h"
+#include "pipe/draw/draw_vertex.h"
+#include "pipe/p_util.h"
+#include "pipe/p_shader_tokens.h"
+
+#define DEBUG_VERTS 0
+
+/**
+ * Triangle edge info
+ */
+struct edge {
+ float dx; /**< X(v1) - X(v0), used only during setup */
+ float dy; /**< Y(v1) - Y(v0), used only during setup */
+ float dxdy; /**< dx/dy */
+ float sx, sy; /**< first sample point coord */
+ int lines; /**< number of lines on this edge */
+};
+
+
+/**
+ * Triangle setup info (derived from draw_stage).
+ * Also used for line drawing (taking some liberties).
+ */
+struct setup_stage {
+ struct draw_stage stage; /**< This must be first (base class) */
+
+ struct softpipe_context *softpipe;
+
+ /* Vertices are just an array of floats making up each attribute in
+ * turn. Currently fixed at 4 floats, but should change in time.
+ * Codegen will help cope with this.
+ */
+ const struct vertex_header *vmax;
+ const struct vertex_header *vmid;
+ const struct vertex_header *vmin;
+ const struct vertex_header *vprovoke;
+
+ struct edge ebot;
+ struct edge etop;
+ struct edge emaj;
+
+ float oneoverarea;
+
+ struct tgsi_interp_coef coef[PIPE_MAX_SHADER_INPUTS];
+ struct tgsi_interp_coef posCoef; /* For Z, W */
+ struct quad_header quad;
+
+ struct {
+ int left[2]; /**< [0] = row0, [1] = row1 */
+ int right[2];
+ int y;
+ unsigned y_flags;
+ unsigned mask; /**< mask of MASK_BOTTOM/TOP_LEFT/RIGHT bits */
+ } span;
+};
+
+
+
+/**
+ * Basically a cast wrapper.
+ */
+static INLINE struct setup_stage *setup_stage( struct draw_stage *stage )
+{
+ return (struct setup_stage *)stage;
+}
+
+
+/**
+ * Clip setup->quad against the scissor/surface bounds.
+ */
+static INLINE void
+quad_clip(struct setup_stage *setup)
+{
+ const struct pipe_scissor_state *cliprect = &setup->softpipe->cliprect;
+ const int minx = (int) cliprect->minx;
+ const int maxx = (int) cliprect->maxx;
+ const int miny = (int) cliprect->miny;
+ const int maxy = (int) cliprect->maxy;
+
+ if (setup->quad.x0 >= maxx ||
+ setup->quad.y0 >= maxy ||
+ setup->quad.x0 + 1 < minx ||
+ setup->quad.y0 + 1 < miny) {
+ /* totally clipped */
+ setup->quad.mask = 0x0;
+ return;
+ }
+ if (setup->quad.x0 < minx)
+ setup->quad.mask &= (MASK_BOTTOM_RIGHT | MASK_TOP_RIGHT);
+ if (setup->quad.y0 < miny)
+ setup->quad.mask &= (MASK_BOTTOM_LEFT | MASK_BOTTOM_RIGHT);
+ if (setup->quad.x0 == maxx - 1)
+ setup->quad.mask &= (MASK_BOTTOM_LEFT | MASK_TOP_LEFT);
+ if (setup->quad.y0 == maxy - 1)
+ setup->quad.mask &= (MASK_TOP_LEFT | MASK_TOP_RIGHT);
+}
+
+
+/**
+ * Emit a quad (pass to next stage) with clipping.
+ */
+static INLINE void
+clip_emit_quad(struct setup_stage *setup)
+{
+ quad_clip(setup);
+ if (setup->quad.mask) {
+ struct softpipe_context *sp = setup->softpipe;
+ sp->quad.first->run(sp->quad.first, &setup->quad);
+ }
+}
+
+
+/**
+ * Emit a quad (pass to next stage). No clipping is done.
+ */
+static INLINE void
+emit_quad( struct setup_stage *setup, int x, int y, unsigned mask )
+{
+ struct softpipe_context *sp = setup->softpipe;
+ setup->quad.x0 = x;
+ setup->quad.y0 = y;
+ setup->quad.mask = mask;
+ sp->quad.first->run(sp->quad.first, &setup->quad);
+}
+
+
+/**
+ * Given an X or Y coordinate, return the block/quad coordinate that it
+ * belongs to.
+ */
+static INLINE int block( int x )
+{
+ return x & ~1;
+}
+
+
+/**
+ * Compute mask which indicates which pixels in the 2x2 quad are actually inside
+ * the triangle's bounds.
+ *
+ * this is pretty nasty... may need to rework flush_spans again to
+ * fix it, if possible.
+ */
+static unsigned calculate_mask( struct setup_stage *setup, int x )
+{
+ unsigned mask = 0x0;
+
+ if (x >= setup->span.left[0] && x < setup->span.right[0])
+ mask |= MASK_TOP_LEFT;
+
+ if (x >= setup->span.left[1] && x < setup->span.right[1])
+ mask |= MASK_BOTTOM_LEFT;
+
+ if (x+1 >= setup->span.left[0] && x+1 < setup->span.right[0])
+ mask |= MASK_TOP_RIGHT;
+
+ if (x+1 >= setup->span.left[1] && x+1 < setup->span.right[1])
+ mask |= MASK_BOTTOM_RIGHT;
+
+ return mask;
+}
+
+
+/**
+ * Render a horizontal span of quads
+ */
+static void flush_spans( struct setup_stage *setup )
+{
+ int minleft, maxright;
+ int x;
+
+ switch (setup->span.y_flags) {
+ case 0x3:
+ /* both odd and even lines written (both quad rows) */
+ minleft = MIN2(setup->span.left[0], setup->span.left[1]);
+ maxright = MAX2(setup->span.right[0], setup->span.right[1]);
+ break;
+
+ case 0x1:
+ /* only even line written (quad top row) */
+ minleft = setup->span.left[0];
+ maxright = setup->span.right[0];
+ break;
+
+ case 0x2:
+ /* only odd line written (quad bottom row) */
+ minleft = setup->span.left[1];
+ maxright = setup->span.right[1];
+ break;
+
+ default:
+ return;
+ }
+
+ /* XXX this loop could be moved into the above switch cases and
+ * calculate_mask() could be simplified a bit...
+ */
+ for (x = block(minleft); x <= block(maxright); x += 2) {
+ emit_quad( setup, x, setup->span.y,
+ calculate_mask( setup, x ) );
+ }
+
+ setup->span.y = 0;
+ setup->span.y_flags = 0;
+ setup->span.right[0] = 0;
+ setup->span.right[1] = 0;
+}
+
+#if DEBUG_VERTS
+static void print_vertex(const struct setup_stage *setup,
+ const struct vertex_header *v)
+{
+ int i;
+ debug_printf("Vertex: (%p)\n", v);
+ for (i = 0; i < setup->quad.nr_attrs; i++) {
+ debug_printf(" %d: %f %f %f %f\n", i,
+ v->data[i][0], v->data[i][1], v->data[i][2], v->data[i][3]);
+ }
+}
+#endif
+
+static boolean setup_sort_vertices( struct setup_stage *setup,
+ const struct prim_header *prim )
+{
+ const struct vertex_header *v0 = prim->v[0];
+ const struct vertex_header *v1 = prim->v[1];
+ const struct vertex_header *v2 = prim->v[2];
+
+#if DEBUG_VERTS
+ debug_printf("Triangle:\n");
+ print_vertex(setup, v0);
+ print_vertex(setup, v1);
+ print_vertex(setup, v2);
+#endif
+
+ setup->vprovoke = v2;
+
+ /* determine bottom to top order of vertices */
+ {
+ float y0 = v0->data[0][1];
+ float y1 = v1->data[0][1];
+ float y2 = v2->data[0][1];
+ if (y0 <= y1) {
+ if (y1 <= y2) {
+ /* y0<=y1<=y2 */
+ setup->vmin = v0;
+ setup->vmid = v1;
+ setup->vmax = v2;
+ }
+ else if (y2 <= y0) {
+ /* y2<=y0<=y1 */
+ setup->vmin = v2;
+ setup->vmid = v0;
+ setup->vmax = v1;
+ }
+ else {
+ /* y0<=y2<=y1 */
+ setup->vmin = v0;
+ setup->vmid = v2;
+ setup->vmax = v1;
+ }
+ }
+ else {
+ if (y0 <= y2) {
+ /* y1<=y0<=y2 */
+ setup->vmin = v1;
+ setup->vmid = v0;
+ setup->vmax = v2;
+ }
+ else if (y2 <= y1) {
+ /* y2<=y1<=y0 */
+ setup->vmin = v2;
+ setup->vmid = v1;
+ setup->vmax = v0;
+ }
+ else {
+ /* y1<=y2<=y0 */
+ setup->vmin = v1;
+ setup->vmid = v2;
+ setup->vmax = v0;
+ }
+ }
+ }
+
+ setup->ebot.dx = setup->vmid->data[0][0] - setup->vmin->data[0][0];
+ setup->ebot.dy = setup->vmid->data[0][1] - setup->vmin->data[0][1];
+ setup->emaj.dx = setup->vmax->data[0][0] - setup->vmin->data[0][0];
+ setup->emaj.dy = setup->vmax->data[0][1] - setup->vmin->data[0][1];
+ setup->etop.dx = setup->vmax->data[0][0] - setup->vmid->data[0][0];
+ setup->etop.dy = setup->vmax->data[0][1] - setup->vmid->data[0][1];
+
+ /*
+ * Compute triangle's area. Use 1/area to compute partial
+ * derivatives of attributes later.
+ *
+ * The area will be the same as prim->det, but the sign may be
+ * different depending on how the vertices get sorted above.
+ *
+ * To determine whether the primitive is front or back facing we
+ * use the prim->det value because its sign is correct.
+ */
+ {
+ const float area = (setup->emaj.dx * setup->ebot.dy -
+ setup->ebot.dx * setup->emaj.dy);
+
+ setup->oneoverarea = 1.0f / area;
+ /*
+ debug_printf("%s one-over-area %f area %f det %f\n",
+ __FUNCTION__, setup->oneoverarea, area, prim->det );
+ */
+ }
+
+ /* We need to know if this is a front or back-facing triangle for:
+ * - the GLSL gl_FrontFacing fragment attribute (bool)
+ * - two-sided stencil test
+ */
+ setup->quad.facing = (prim->det > 0.0) ^ (setup->softpipe->rasterizer->front_winding == PIPE_WINDING_CW);
+
+ return TRUE;
+}
+
+
+/**
+ * Compute a0 for a constant-valued coefficient (GL_FLAT shading).
+ * The value value comes from vertex->data[slot][i].
+ * The result will be put into setup->coef[slot].a0[i].
+ * \param slot which attribute slot
+ * \param i which component of the slot (0..3)
+ */
+static void const_coeff( struct setup_stage *setup,
+ struct tgsi_interp_coef *coef,
+ uint vertSlot, uint i)
+{
+ assert(i <= 3);
+
+ coef->dadx[i] = 0;
+ coef->dady[i] = 0;
+
+ /* need provoking vertex info!
+ */
+ coef->a0[i] = setup->vprovoke->data[vertSlot][i];
+}
+
+
+/**
+ * Compute a0, dadx and dady for a linearly interpolated coefficient,
+ * for a triangle.
+ */
+static void tri_linear_coeff( struct setup_stage *setup,
+ struct tgsi_interp_coef *coef,
+ uint vertSlot, uint i)
+{
+ float botda = setup->vmid->data[vertSlot][i] - setup->vmin->data[vertSlot][i];
+ float majda = setup->vmax->data[vertSlot][i] - setup->vmin->data[vertSlot][i];
+ float a = setup->ebot.dy * majda - botda * setup->emaj.dy;
+ float b = setup->emaj.dx * botda - majda * setup->ebot.dx;
+ float dadx = a * setup->oneoverarea;
+ float dady = b * setup->oneoverarea;
+
+ assert(i <= 3);
+
+ coef->dadx[i] = dadx;
+ coef->dady[i] = dady;
+
+ /* calculate a0 as the value which would be sampled for the
+ * fragment at (0,0), taking into account that we want to sample at
+ * pixel centers, in other words (0.5, 0.5).
+ *
+ * this is neat but unfortunately not a good way to do things for
+ * triangles with very large values of dadx or dady as it will
+ * result in the subtraction and re-addition from a0 of a very
+ * large number, which means we'll end up loosing a lot of the
+ * fractional bits and precision from a0. the way to fix this is
+ * to define a0 as the sample at a pixel center somewhere near vmin
+ * instead - i'll switch to this later.
+ */
+ coef->a0[i] = (setup->vmin->data[vertSlot][i] -
+ (dadx * (setup->vmin->data[0][0] - 0.5f) +
+ dady * (setup->vmin->data[0][1] - 0.5f)));
+
+ /*
+ debug_printf("attr[%d].%c: %f dx:%f dy:%f\n",
+ slot, "xyzw"[i],
+ setup->coef[slot].a0[i],
+ setup->coef[slot].dadx[i],
+ setup->coef[slot].dady[i]);
+ */
+}
+
+
+/**
+ * Compute a0, dadx and dady for a perspective-corrected interpolant,
+ * for a triangle.
+ * We basically multiply the vertex value by 1/w before computing
+ * the plane coefficients (a0, dadx, dady).
+ * Later, when we compute the value at a particular fragment position we'll
+ * divide the interpolated value by the interpolated W at that fragment.
+ */
+static void tri_persp_coeff( struct setup_stage *setup,
+ struct tgsi_interp_coef *coef,
+ uint vertSlot, uint i)
+{
+ /* premultiply by 1/w (v->data[0][3] is always W):
+ */
+ float mina = setup->vmin->data[vertSlot][i] * setup->vmin->data[0][3];
+ float mida = setup->vmid->data[vertSlot][i] * setup->vmid->data[0][3];
+ float maxa = setup->vmax->data[vertSlot][i] * setup->vmax->data[0][3];
+ float botda = mida - mina;
+ float majda = maxa - mina;
+ float a = setup->ebot.dy * majda - botda * setup->emaj.dy;
+ float b = setup->emaj.dx * botda - majda * setup->ebot.dx;
+ float dadx = a * setup->oneoverarea;
+ float dady = b * setup->oneoverarea;
+
+ /*
+ debug_printf("tri persp %d,%d: %f %f %f\n", vertSlot, i,
+ setup->vmin->data[vertSlot][i],
+ setup->vmid->data[vertSlot][i],
+ setup->vmax->data[vertSlot][i]
+ );
+ */
+ assert(i <= 3);
+
+ coef->dadx[i] = dadx;
+ coef->dady[i] = dady;
+ coef->a0[i] = (mina -
+ (dadx * (setup->vmin->data[0][0] - 0.5f) +
+ dady * (setup->vmin->data[0][1] - 0.5f)));
+}
+
+
+/**
+ * Special coefficient setup for gl_FragCoord.
+ * X and Y are trivial, though Y has to be inverted for OpenGL.
+ * Z and W are copied from posCoef which should have already been computed.
+ * We could do a bit less work if we'd examine gl_FragCoord's swizzle mask.
+ */
+static void
+setup_fragcoord_coeff(struct setup_stage *setup)
+{
+ /*X*/
+ setup->coef[0].a0[0] = 0;
+ setup->coef[0].dadx[0] = 1.0;
+ setup->coef[0].dady[0] = 0.0;
+ /*Y*/
+ if (setup->softpipe->rasterizer->origin_lower_left) {
+ /* y=0=bottom */
+ const int winHeight = setup->softpipe->framebuffer.cbufs[0]->height;
+ setup->coef[0].a0[1] = (float) (winHeight - 1);
+ setup->coef[0].dady[1] = -1.0;
+ }
+ else {
+ /* y=0=top */
+ setup->coef[0].a0[1] = 0.0;
+ setup->coef[0].dady[1] = 1.0;
+ }
+ setup->coef[0].dadx[1] = 0.0;
+ /*Z*/
+ setup->coef[0].a0[2] = setup->posCoef.a0[2];
+ setup->coef[0].dadx[2] = setup->posCoef.dadx[2];
+ setup->coef[0].dady[2] = setup->posCoef.dady[2];
+ /*W*/
+ setup->coef[0].a0[3] = setup->posCoef.a0[3];
+ setup->coef[0].dadx[3] = setup->posCoef.dadx[3];
+ setup->coef[0].dady[3] = setup->posCoef.dady[3];
+}
+
+
+
+/**
+ * Compute the setup->coef[] array dadx, dady, a0 values.
+ * Must be called after setup->vmin,vmid,vmax,vprovoke are initialized.
+ */
+static void setup_tri_coefficients( struct setup_stage *setup )
+{
+ struct softpipe_context *softpipe = setup->softpipe;
+ const struct pipe_shader_state *fs = &softpipe->fs->shader;
+ const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe);
+ uint fragSlot;
+
+ /* z and w are done by linear interpolation:
+ */
+ tri_linear_coeff(setup, &setup->posCoef, 0, 2);
+ tri_linear_coeff(setup, &setup->posCoef, 0, 3);
+
+ /* setup interpolation for all the remaining attributes:
+ */
+ for (fragSlot = 0; fragSlot < fs->num_inputs; fragSlot++) {
+ const uint vertSlot = vinfo->src_index[fragSlot];
+ uint j;
+
+ switch (vinfo->interp_mode[fragSlot]) {
+ case INTERP_CONSTANT:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ const_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_LINEAR:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ tri_linear_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_PERSPECTIVE:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ tri_persp_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_POS:
+ assert(fragSlot == 0);
+ setup_fragcoord_coeff(setup);
+ break;
+ default:
+ assert(0);
+ }
+
+ if (fs->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FOG) {
+ /* FOG.y = front/back facing XXX fix this */
+ setup->coef[fragSlot].a0[1] = 1.0f - setup->quad.facing;
+ setup->coef[fragSlot].dadx[1] = 0.0;
+ setup->coef[fragSlot].dady[1] = 0.0;
+ }
+ }
+}
+
+
+
+static void setup_tri_edges( struct setup_stage *setup )
+{
+ float vmin_x = setup->vmin->data[0][0] + 0.5f;
+ float vmid_x = setup->vmid->data[0][0] + 0.5f;
+
+ float vmin_y = setup->vmin->data[0][1] - 0.5f;
+ float vmid_y = setup->vmid->data[0][1] - 0.5f;
+ float vmax_y = setup->vmax->data[0][1] - 0.5f;
+
+ setup->emaj.sy = CEILF(vmin_y);
+ setup->emaj.lines = (int) CEILF(vmax_y - setup->emaj.sy);
+ setup->emaj.dxdy = setup->emaj.dx / setup->emaj.dy;
+ setup->emaj.sx = vmin_x + (setup->emaj.sy - vmin_y) * setup->emaj.dxdy;
+
+ setup->etop.sy = CEILF(vmid_y);
+ setup->etop.lines = (int) CEILF(vmax_y - setup->etop.sy);
+ setup->etop.dxdy = setup->etop.dx / setup->etop.dy;
+ setup->etop.sx = vmid_x + (setup->etop.sy - vmid_y) * setup->etop.dxdy;
+
+ setup->ebot.sy = CEILF(vmin_y);
+ setup->ebot.lines = (int) CEILF(vmid_y - setup->ebot.sy);
+ setup->ebot.dxdy = setup->ebot.dx / setup->ebot.dy;
+ setup->ebot.sx = vmin_x + (setup->ebot.sy - vmin_y) * setup->ebot.dxdy;
+}
+
+
+/**
+ * Render the upper or lower half of a triangle.
+ * Scissoring/cliprect is applied here too.
+ */
+static void subtriangle( struct setup_stage *setup,
+ struct edge *eleft,
+ struct edge *eright,
+ unsigned lines )
+{
+ const struct pipe_scissor_state *cliprect = &setup->softpipe->cliprect;
+ const int minx = (int) cliprect->minx;
+ const int maxx = (int) cliprect->maxx;
+ const int miny = (int) cliprect->miny;
+ const int maxy = (int) cliprect->maxy;
+ int y, start_y, finish_y;
+ int sy = (int)eleft->sy;
+
+ assert((int)eleft->sy == (int) eright->sy);
+
+ /* clip top/bottom */
+ start_y = sy;
+ finish_y = sy + lines;
+
+ if (start_y < miny)
+ start_y = miny;
+
+ if (finish_y > maxy)
+ finish_y = maxy;
+
+ start_y -= sy;
+ finish_y -= sy;
+
+ /*
+ debug_printf("%s %d %d\n", __FUNCTION__, start_y, finish_y);
+ */
+
+ for (y = start_y; y < finish_y; y++) {
+
+ /* avoid accumulating adds as floats don't have the precision to
+ * accurately iterate large triangle edges that way. luckily we
+ * can just multiply these days.
+ *
+ * this is all drowned out by the attribute interpolation anyway.
+ */
+ int left = (int)(eleft->sx + y * eleft->dxdy);
+ int right = (int)(eright->sx + y * eright->dxdy);
+
+ /* clip left/right */
+ if (left < minx)
+ left = minx;
+ if (right > maxx)
+ right = maxx;
+
+ if (left < right) {
+ int _y = sy + y;
+ if (block(_y) != setup->span.y) {
+ flush_spans(setup);
+ setup->span.y = block(_y);
+ }
+
+ setup->span.left[_y&1] = left;
+ setup->span.right[_y&1] = right;
+ setup->span.y_flags |= 1<<(_y&1);
+ }
+ }
+
+
+ /* save the values so that emaj can be restarted:
+ */
+ eleft->sx += lines * eleft->dxdy;
+ eright->sx += lines * eright->dxdy;
+ eleft->sy += lines;
+ eright->sy += lines;
+}
+
+
+/**
+ * Do setup for triangle rasterization, then render the triangle.
+ */
+static void setup_tri( struct draw_stage *stage,
+ struct prim_header *prim )
+{
+ struct setup_stage *setup = setup_stage( stage );
+
+ /*
+ debug_printf("%s\n", __FUNCTION__ );
+ */
+
+ setup_sort_vertices( setup, prim );
+ setup_tri_coefficients( setup );
+ setup_tri_edges( setup );
+
+ setup->quad.prim = PRIM_TRI;
+
+ setup->span.y = 0;
+ setup->span.y_flags = 0;
+ setup->span.right[0] = 0;
+ setup->span.right[1] = 0;
+ /* setup->span.z_mode = tri_z_mode( setup->ctx ); */
+
+ /* init_constant_attribs( setup ); */
+
+ if (setup->oneoverarea < 0.0) {
+ /* emaj on left:
+ */
+ subtriangle( setup, &setup->emaj, &setup->ebot, setup->ebot.lines );
+ subtriangle( setup, &setup->emaj, &setup->etop, setup->etop.lines );
+ }
+ else {
+ /* emaj on right:
+ */
+ subtriangle( setup, &setup->ebot, &setup->emaj, setup->ebot.lines );
+ subtriangle( setup, &setup->etop, &setup->emaj, setup->etop.lines );
+ }
+
+ flush_spans( setup );
+}
+
+
+
+/**
+ * Compute a0, dadx and dady for a linearly interpolated coefficient,
+ * for a line.
+ */
+static void
+line_linear_coeff(struct setup_stage *setup,
+ struct tgsi_interp_coef *coef,
+ uint vertSlot, uint i)
+{
+ const float da = setup->vmax->data[vertSlot][i] - setup->vmin->data[vertSlot][i];
+ const float dadx = da * setup->emaj.dx * setup->oneoverarea;
+ const float dady = da * setup->emaj.dy * setup->oneoverarea;
+ coef->dadx[i] = dadx;
+ coef->dady[i] = dady;
+ coef->a0[i] = (setup->vmin->data[vertSlot][i] -
+ (dadx * (setup->vmin->data[0][0] - 0.5f) +
+ dady * (setup->vmin->data[0][1] - 0.5f)));
+}
+
+
+/**
+ * Compute a0, dadx and dady for a perspective-corrected interpolant,
+ * for a line.
+ */
+static void
+line_persp_coeff(struct setup_stage *setup,
+ struct tgsi_interp_coef *coef,
+ uint vertSlot, uint i)
+{
+ /* XXX double-check/verify this arithmetic */
+ const float a0 = setup->vmin->data[vertSlot][i] * setup->vmin->data[0][3];
+ const float a1 = setup->vmax->data[vertSlot][i] * setup->vmax->data[0][3];
+ const float da = a1 - a0;
+ const float dadx = da * setup->emaj.dx * setup->oneoverarea;
+ const float dady = da * setup->emaj.dy * setup->oneoverarea;
+ coef->dadx[i] = dadx;
+ coef->dady[i] = dady;
+ coef->a0[i] = (setup->vmin->data[vertSlot][i] -
+ (dadx * (setup->vmin->data[0][0] - 0.5f) +
+ dady * (setup->vmin->data[0][1] - 0.5f)));
+}
+
+
+/**
+ * Compute the setup->coef[] array dadx, dady, a0 values.
+ * Must be called after setup->vmin,vmax are initialized.
+ */
+static INLINE void
+setup_line_coefficients(struct setup_stage *setup, struct prim_header *prim)
+{
+ struct softpipe_context *softpipe = setup->softpipe;
+ const struct pipe_shader_state *fs = &setup->softpipe->fs->shader;
+ const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe);
+ uint fragSlot;
+
+ /* use setup->vmin, vmax to point to vertices */
+ setup->vprovoke = prim->v[1];
+ setup->vmin = prim->v[0];
+ setup->vmax = prim->v[1];
+
+ setup->emaj.dx = setup->vmax->data[0][0] - setup->vmin->data[0][0];
+ setup->emaj.dy = setup->vmax->data[0][1] - setup->vmin->data[0][1];
+ /* NOTE: this is not really 1/area */
+ setup->oneoverarea = 1.0f / (setup->emaj.dx * setup->emaj.dx +
+ setup->emaj.dy * setup->emaj.dy);
+
+ /* z and w are done by linear interpolation:
+ */
+ line_linear_coeff(setup, &setup->posCoef, 0, 2);
+ line_linear_coeff(setup, &setup->posCoef, 0, 3);
+
+ /* setup interpolation for all the remaining attributes:
+ */
+ for (fragSlot = 0; fragSlot < fs->num_inputs; fragSlot++) {
+ const uint vertSlot = vinfo->src_index[fragSlot];
+ uint j;
+
+ switch (vinfo->interp_mode[fragSlot]) {
+ case INTERP_CONSTANT:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ const_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_LINEAR:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ line_linear_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_PERSPECTIVE:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ line_persp_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_POS:
+ assert(fragSlot == 0);
+ assert(0); /* XXX fix this: */
+ setup_fragcoord_coeff(setup);
+ break;
+ default:
+ assert(0);
+ }
+
+ if (fs->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FOG) {
+ /* FOG.y = front/back facing XXX fix this */
+ setup->coef[fragSlot].a0[1] = 1.0f - setup->quad.facing;
+ setup->coef[fragSlot].dadx[1] = 0.0;
+ setup->coef[fragSlot].dady[1] = 0.0;
+ }
+ }
+}
+
+
+/**
+ * Plot a pixel in a line segment.
+ */
+static INLINE void
+plot(struct setup_stage *setup, int x, int y)
+{
+ const int iy = y & 1;
+ const int ix = x & 1;
+ const int quadX = x - ix;
+ const int quadY = y - iy;
+ const int mask = (1 << ix) << (2 * iy);
+
+ if (quadX != setup->quad.x0 ||
+ quadY != setup->quad.y0)
+ {
+ /* flush prev quad, start new quad */
+
+ if (setup->quad.x0 != -1)
+ clip_emit_quad(setup);
+
+ setup->quad.x0 = quadX;
+ setup->quad.y0 = quadY;
+ setup->quad.mask = 0x0;
+ }
+
+ setup->quad.mask |= mask;
+}
+
+
+/**
+ * Do setup for line rasterization, then render the line.
+ * Single-pixel width, no stipple, etc. We rely on the 'draw' module
+ * to handle stippling and wide lines.
+ */
+static void
+setup_line(struct draw_stage *stage, struct prim_header *prim)
+{
+ const struct vertex_header *v0 = prim->v[0];
+ const struct vertex_header *v1 = prim->v[1];
+ struct setup_stage *setup = setup_stage( stage );
+ int x0 = (int) v0->data[0][0];
+ int x1 = (int) v1->data[0][0];
+ int y0 = (int) v0->data[0][1];
+ int y1 = (int) v1->data[0][1];
+ int dx = x1 - x0;
+ int dy = y1 - y0;
+ int xstep, ystep;
+
+ if (dx == 0 && dy == 0)
+ return;
+
+ setup_line_coefficients(setup, prim);
+
+ if (dx < 0) {
+ dx = -dx; /* make positive */
+ xstep = -1;
+ }
+ else {
+ xstep = 1;
+ }
+
+ if (dy < 0) {
+ dy = -dy; /* make positive */
+ ystep = -1;
+ }
+ else {
+ ystep = 1;
+ }
+
+ assert(dx >= 0);
+ assert(dy >= 0);
+
+ setup->quad.x0 = setup->quad.y0 = -1;
+ setup->quad.mask = 0x0;
+ setup->quad.prim = PRIM_LINE;
+ /* XXX temporary: set coverage to 1.0 so the line appears
+ * if AA mode happens to be enabled.
+ */
+ setup->quad.coverage[0] =
+ setup->quad.coverage[1] =
+ setup->quad.coverage[2] =
+ setup->quad.coverage[3] = 1.0;
+
+ if (dx > dy) {
+ /*** X-major line ***/
+ int i;
+ const int errorInc = dy + dy;
+ int error = errorInc - dx;
+ const int errorDec = error - dx;
+
+ for (i = 0; i < dx; i++) {
+ plot(setup, x0, y0);
+
+ x0 += xstep;
+ if (error < 0) {
+ error += errorInc;
+ }
+ else {
+ error += errorDec;
+ y0 += ystep;
+ }
+ }
+ }
+ else {
+ /*** Y-major line ***/
+ int i;
+ const int errorInc = dx + dx;
+ int error = errorInc - dy;
+ const int errorDec = error - dy;
+
+ for (i = 0; i < dy; i++) {
+ plot(setup, x0, y0);
+
+ y0 += ystep;
+ if (error < 0) {
+ error += errorInc;
+ }
+ else {
+ error += errorDec;
+ x0 += xstep;
+ }
+ }
+ }
+
+ /* draw final quad */
+ if (setup->quad.mask) {
+ clip_emit_quad(setup);
+ }
+}
+
+
+static void
+point_persp_coeff(struct setup_stage *setup,
+ const struct vertex_header *vert,
+ struct tgsi_interp_coef *coef,
+ uint vertSlot, uint i)
+{
+ assert(i <= 3);
+ coef->dadx[i] = 0.0F;
+ coef->dady[i] = 0.0F;
+ coef->a0[i] = vert->data[vertSlot][i] * vert->data[0][3];
+}
+
+
+/**
+ * Do setup for point rasterization, then render the point.
+ * Round or square points...
+ * XXX could optimize a lot for 1-pixel points.
+ */
+static void
+setup_point(struct draw_stage *stage, struct prim_header *prim)
+{
+ struct setup_stage *setup = setup_stage( stage );
+ struct softpipe_context *softpipe = setup->softpipe;
+ const struct pipe_shader_state *fs = &softpipe->fs->shader;
+ const struct vertex_header *v0 = prim->v[0];
+ const int sizeAttr = setup->softpipe->psize_slot;
+ const float size
+ = sizeAttr > 0 ? v0->data[sizeAttr][0]
+ : setup->softpipe->rasterizer->point_size;
+ const float halfSize = 0.5F * size;
+ const boolean round = (boolean) setup->softpipe->rasterizer->point_smooth;
+ const float x = v0->data[0][0]; /* Note: data[0] is always position */
+ const float y = v0->data[0][1];
+ const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe);
+ uint fragSlot;
+
+ /* For points, all interpolants are constant-valued.
+ * However, for point sprites, we'll need to setup texcoords appropriately.
+ * XXX: which coefficients are the texcoords???
+ * We may do point sprites as textured quads...
+ *
+ * KW: We don't know which coefficients are texcoords - ultimately
+ * the choice of what interpolation mode to use for each attribute
+ * should be determined by the fragment program, using
+ * per-attribute declaration statements that include interpolation
+ * mode as a parameter. So either the fragment program will have
+ * to be adjusted for pointsprite vs normal point behaviour, or
+ * otherwise a special interpolation mode will have to be defined
+ * which matches the required behaviour for point sprites. But -
+ * the latter is not a feature of normal hardware, and as such
+ * probably should be ruled out on that basis.
+ */
+ setup->vprovoke = prim->v[0];
+
+ /* setup Z, W */
+ const_coeff(setup, &setup->posCoef, 0, 2);
+ const_coeff(setup, &setup->posCoef, 0, 3);
+
+ for (fragSlot = 0; fragSlot < fs->num_inputs; fragSlot++) {
+ const uint vertSlot = vinfo->src_index[fragSlot];
+ uint j;
+
+ switch (vinfo->interp_mode[fragSlot]) {
+ case INTERP_CONSTANT:
+ /* fall-through */
+ case INTERP_LINEAR:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ const_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_PERSPECTIVE:
+ for (j = 0; j < NUM_CHANNELS; j++)
+ point_persp_coeff(setup, setup->vprovoke,
+ &setup->coef[fragSlot], vertSlot, j);
+ break;
+ case INTERP_POS:
+ assert(fragSlot == 0);
+ assert(0); /* XXX fix this: */
+ setup_fragcoord_coeff(setup);
+ break;
+ default:
+ assert(0);
+ }
+
+ if (fs->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FOG) {
+ /* FOG.y = front/back facing XXX fix this */
+ setup->coef[fragSlot].a0[1] = 1.0f - setup->quad.facing;
+ setup->coef[fragSlot].dadx[1] = 0.0;
+ setup->coef[fragSlot].dady[1] = 0.0;
+ }
+ }
+
+ setup->quad.prim = PRIM_POINT;
+
+ if (halfSize <= 0.5 && !round) {
+ /* special case for 1-pixel points */
+ const int ix = ((int) x) & 1;
+ const int iy = ((int) y) & 1;
+ setup->quad.x0 = (int) x - ix;
+ setup->quad.y0 = (int) y - iy;
+ setup->quad.mask = (1 << ix) << (2 * iy);
+ clip_emit_quad(setup);
+ }
+ else {
+ if (round) {
+ /* rounded points */
+ const int ixmin = block((int) (x - halfSize));
+ const int ixmax = block((int) (x + halfSize));
+ const int iymin = block((int) (y - halfSize));
+ const int iymax = block((int) (y + halfSize));
+ const float rmin = halfSize - 0.7071F; /* 0.7071 = sqrt(2)/2 */
+ const float rmax = halfSize + 0.7071F;
+ const float rmin2 = MAX2(0.0F, rmin * rmin);
+ const float rmax2 = rmax * rmax;
+ const float cscale = 1.0F / (rmax2 - rmin2);
+ int ix, iy;
+
+ for (iy = iymin; iy <= iymax; iy += 2) {
+ for (ix = ixmin; ix <= ixmax; ix += 2) {
+ float dx, dy, dist2, cover;
+
+ setup->quad.mask = 0x0;
+
+ dx = (ix + 0.5f) - x;
+ dy = (iy + 0.5f) - y;
+ dist2 = dx * dx + dy * dy;
+ if (dist2 <= rmax2) {
+ cover = 1.0F - (dist2 - rmin2) * cscale;
+ setup->quad.coverage[QUAD_TOP_LEFT] = MIN2(cover, 1.0f);
+ setup->quad.mask |= MASK_TOP_LEFT;
+ }
+
+ dx = (ix + 1.5f) - x;
+ dy = (iy + 0.5f) - y;
+ dist2 = dx * dx + dy * dy;
+ if (dist2 <= rmax2) {
+ cover = 1.0F - (dist2 - rmin2) * cscale;
+ setup->quad.coverage[QUAD_TOP_RIGHT] = MIN2(cover, 1.0f);
+ setup->quad.mask |= MASK_TOP_RIGHT;
+ }
+
+ dx = (ix + 0.5f) - x;
+ dy = (iy + 1.5f) - y;
+ dist2 = dx * dx + dy * dy;
+ if (dist2 <= rmax2) {
+ cover = 1.0F - (dist2 - rmin2) * cscale;
+ setup->quad.coverage[QUAD_BOTTOM_LEFT] = MIN2(cover, 1.0f);
+ setup->quad.mask |= MASK_BOTTOM_LEFT;
+ }
+
+ dx = (ix + 1.5f) - x;
+ dy = (iy + 1.5f) - y;
+ dist2 = dx * dx + dy * dy;
+ if (dist2 <= rmax2) {
+ cover = 1.0F - (dist2 - rmin2) * cscale;
+ setup->quad.coverage[QUAD_BOTTOM_RIGHT] = MIN2(cover, 1.0f);
+ setup->quad.mask |= MASK_BOTTOM_RIGHT;
+ }
+
+ if (setup->quad.mask) {
+ setup->quad.x0 = ix;
+ setup->quad.y0 = iy;
+ clip_emit_quad(setup);
+ }
+ }
+ }
+ }
+ else {
+ /* square points */
+ const int xmin = (int) (x + 0.75 - halfSize);
+ const int ymin = (int) (y + 0.25 - halfSize);
+ const int xmax = xmin + (int) size;
+ const int ymax = ymin + (int) size;
+ /* XXX could apply scissor to xmin,ymin,xmax,ymax now */
+ const int ixmin = block(xmin);
+ const int ixmax = block(xmax - 1);
+ const int iymin = block(ymin);
+ const int iymax = block(ymax - 1);
+ int ix, iy;
+
+ /*
+ debug_printf("(%f, %f) -> X:%d..%d Y:%d..%d\n", x, y, xmin, xmax,ymin,ymax);
+ */
+ for (iy = iymin; iy <= iymax; iy += 2) {
+ uint rowMask = 0xf;
+ if (iy < ymin) {
+ /* above the top edge */
+ rowMask &= (MASK_BOTTOM_LEFT | MASK_BOTTOM_RIGHT);
+ }
+ if (iy + 1 >= ymax) {
+ /* below the bottom edge */
+ rowMask &= (MASK_TOP_LEFT | MASK_TOP_RIGHT);
+ }
+
+ for (ix = ixmin; ix <= ixmax; ix += 2) {
+ uint mask = rowMask;
+
+ if (ix < xmin) {
+ /* fragment is past left edge of point, turn off left bits */
+ mask &= (MASK_BOTTOM_RIGHT | MASK_TOP_RIGHT);
+ }
+ if (ix + 1 >= xmax) {
+ /* past the right edge */
+ mask &= (MASK_BOTTOM_LEFT | MASK_TOP_LEFT);
+ }
+
+ setup->quad.mask = mask;
+ setup->quad.x0 = ix;
+ setup->quad.y0 = iy;
+ clip_emit_quad(setup);
+ }
+ }
+ }
+ }
+}
+
+
+
+static void setup_begin( struct draw_stage *stage )
+{
+ struct setup_stage *setup = setup_stage(stage);
+ struct softpipe_context *sp = setup->softpipe;
+ const struct pipe_shader_state *fs = &setup->softpipe->fs->shader;
+
+ setup->quad.nr_attrs = fs->num_inputs;
+
+ sp->quad.first->begin(sp->quad.first);
+
+ stage->point = setup_point;
+ stage->line = setup_line;
+ stage->tri = setup_tri;
+}
+
+
+static void setup_first_point( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ setup_begin(stage);
+ stage->point( stage, header );
+}
+
+static void setup_first_line( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ setup_begin(stage);
+ stage->line( stage, header );
+}
+
+
+static void setup_first_tri( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ setup_begin(stage);
+ stage->tri( stage, header );
+}
+
+
+
+static void setup_flush( struct draw_stage *stage,
+ unsigned flags )
+{
+ stage->point = setup_first_point;
+ stage->line = setup_first_line;
+ stage->tri = setup_first_tri;
+}
+
+
+static void reset_stipple_counter( struct draw_stage *stage )
+{
+}
+
+
+static void render_destroy( struct draw_stage *stage )
+{
+ FREE( stage );
+}
+
+
+/**
+ * Create a new primitive setup/render stage.
+ */
+struct draw_stage *sp_draw_render_stage( struct softpipe_context *softpipe )
+{
+ struct setup_stage *setup = CALLOC_STRUCT(setup_stage);
+
+ setup->softpipe = softpipe;
+ setup->stage.draw = softpipe->draw;
+ setup->stage.point = setup_first_point;
+ setup->stage.line = setup_first_line;
+ setup->stage.tri = setup_first_tri;
+ setup->stage.flush = setup_flush;
+ setup->stage.reset_stipple_counter = reset_stipple_counter;
+ setup->stage.destroy = render_destroy;
+
+ setup->quad.coef = setup->coef;
+ setup->quad.posCoef = &setup->posCoef;
+
+ return &setup->stage;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-13 20:29:00 +0000